Only throw when both `pkg.now` and `now.json` are present

Fixes failing test case.

lib/read-metadata.js

@@ -23,12 +23,14 @@ async function readMetaData(path, {
 }) {
   let pkg = {}
   let nowConfig = {}
+  let hasNowJson = false
 
   let name
   let description
 
   try {
     nowConfig = JSON.parse(await readFile(resolvePath(path, 'now.json')))
+    hasNowJson = true
   } catch (err) {
     // if the file doesn't exist then that's fine; any other error bubbles up
     if (err.code !== 'ENOENT') {
@@ -127,11 +129,15 @@ async function readMetaData(path, {
     name = deploymentName
   }
 
-  // if the project has both a `now.json` and `now` Object in the `package.json`
-  // file, then fail hard and let the user know that they need to pick one or the
-  // other
   if (pkg.now) {
-    throw new Error('Refusing to proceed with multiple Now configurations (`now.json` and `package.json`). Please pick only one, then try again!')
+    // if the project has both a `now.json` and `now` Object in the `package.json`
+    // file, then fail hard and let the user know that they need to pick one or the
+    // other
+    if (hasNowJson) {
+      throw new Error('Refusing to proceed with multiple Now configurations (`now.json` and `package.json`). Please pick only one, then try again!')
+    } else {
+      nowConfig = pkg.now
+    }
   }
 
   return {